Ore-crusher



\ iour or more sections, for convenience in conl trough, which is Vshaped in cross-section,

i 3 To a/ZZ whom t may concern:

. Nirnn STATES PA'rnNr @rincer JACOB CHARLES wrswnLL, `onirunronn,MASSACHUSETTS.

ORE-CRUSHER.

SPECIFICATION `forming part of Letters Patent No. 296,096, dated April1, 1884.

Application filed Xovrmher 8, 1F83. (No model.)

. Be it known thatl, JACOB CHARLES WIS- WELL, a citizen of the UnitedStates, residing at Medford, in the county of Middlesex and State ofMassachusetts, have invented certain new and useful Improvements inOre-Crushers; and I do hereby declare the following to be a l full,clear, and exact `description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to lettersor figures of reference marked thereon, `which form a part of thisoperation becomes necessary.

, specification.

` z hereinafter described and cla1med,1n a class of Thisinvention'consists in improvements,

mills `for crushing ores or other hard substances, in which a series ofrollers pivoted to a rotary Carriage travel in a circular path about astationary bed, and operate to reduce the material by crushing action.

The drawings accompanying this specification represent, in Figure 1, aplan, and Fig. 2

a cross-section, of a mill embodying my improvements. Fig. Sisa detailView, on an en- `larged scale, of one of the springs 71y and adj acentdevices.

In said` drawings, A represents the base or bed of the mill, the samebeing of cast-iron or stone and circular in form, and preferably in thistrough being formed in the top of the bed A, `near the circumference ofthe latter. At

i l the bottoniof the trough 13,1 provide at intervals passages c u,8vo., to permit of taking off the amalgam, andof escape of materialsused in cleaningthe trough, when the latter The upper portion of thetrough is continued by annular curbings c c,oi' wood or other material,and in the outer one, c, of such curbings I form i ertures d d, Sie.,each of which islcovered by per end of said shaft beingj ournaled in abeara screen, e, of suitablematerial.

`C represents a vertical shaft, which at bottom is stepped in a block,D, secured to the top of` the` bed A, centrally of the latter, the upiing supported by a horizontal beam, E, or

other object, in such manner as to be capable of a certain amount ofvertical slip. The shaft C is rotated by a miter-gear, F, secured" toits upper part, which engages with and is driven by a similar gear, G,secured toa countershaft-H, suitably supported and driven. To the lowerpart of the shaft C, I secure a horizontal carriage, I, and in thiscarriage four axles, J J J J, have their outer bearings, the inner endof each axle being stepped in a bearing secured to the shaft. To theextreme outer end of each axle I secure a circular roller, K, which isadapted to revolve in the trough B; hence the periphery of each rolleris of a V form in cross-section, corresponding to the trough. The innerhalf, f, of each roller ts closely to the corresponding side, g, of thetrough B,"and isa conic frustum of which the apex is the axis ofvrotation of the shaft C. Owing to this form of the periphery of theinner half of the roller, and Vthecorresponding shape of the inner sideof the trough, such periphery adapts itself naturally to the bed andtraverses the latter with ease, free from slip and lost motion, whichreduces the fric-` tion to the minimum, for which reason the rollers canbe run very rapidly and this, in addition to the comparatively largenumber of rollers employed, enables me to reduce the material Yveryrapidly and economically. If the outer half of each roller tted snuglyto the trough, a certain slip and abrasive action would ensue betweenthe two, and to avoid this I separate this portion of the rollerslightly from thebottom of the outer side of the trough. A certainamount of preliminary crushing is effected by the outer half of eachroller; but the bulk of such crushing is effected by the inner half. Thematerial, as it is reduced to the requisitedegree of neness,is thrownupward and outward bycentrifugal force of the revolving rollers andescapes through the apertures d d, Sto., in the wall of the trough, andis screened i-n passing the screens e e, &c. To relieve the strain onthe bearings of shafts J incident to grinding, I make use of springs h,which are set into recesses on the under Side of the carriage I, andbear against the outer bearings of said shafts. The pressure of saidsprings-may be regulated by means of adjusting-screws h', as illustratedin Figs. l and l3,

IOO

rIhis mill is designed to operate strictly by crushing the material,which leaves the particles ina normal crystal form. This result isveryiinportant in the reduction and preparation oi'auri fero ussul phurets and other classes of ores which are to be concentrated and theprecious metal collected by any of the mercurial processes.

Mills which operate to reduce the material by attrit-ion or abrasionleave the particles in a very unfavorable condition for concentratingand amalgamation, as the sharp corners are worn off; hence theimportance of a mill which operates strictly to crush the material andpreserve the crystal form ofthe particles.

I am aware that itis not broadly new to employ a series ofgrinding-rolls having V-shaped peripheriesifor the purpose of grindingore,

said rolls revolving together and rotating individually in a circular Vshaped groove, l which receives the ore to be ground; and therefre Idonot claim the same,- nor do I claim, 1

broadly, the use'of a curbing to extend such a groove upward, noroutlets for the amalgam, nor openings and screens for allowing the exitof comminuted ore; but

What I do claim is- The combination of a series of crushingrollershaving V-shaped peripheries,and horizontal shafts on which said rollersare mounted, with a carriage in which said shafts are journaled at theirouter bearing-points, a vertical shaft 'in which the inner ends of saidhorizontal shafts are journaled, springs which are interposed betweensaid carriage and said horizontal shafts, and a stationary bed having acircular V-shaped groove in which said rollers travel, substantially asset forth.

In testimony whereof I affix mysignatnre in presence of two witnesses.

JACOB CHARLES VISWELL. Vitnesses:

F. CURTIS, A. F. I-IAYDEN.

